Inverters are the silent workhorses that convert power from devices like solar panels and batteries into usable power. There’s been considerable innovation around solar panel inverters in recent years, as some solar roofs have started moving from a single large central inverter to smaller “microinverters” embedded on each panel. But now year-and-a-half-old chip startup Empower Micro Systems has been pushing that solar inverter innovation even farther and has developed a new low voltage solar microinverter based on its new chip designs that it said
costs less and is more reliable and efficient than the current ones on the market.
Empower Micro Systems CCO Jon Bonanno told me that the company’s inverter tech “is a quantum change in how solar is done.” It can be attached to a solar panel system, on the rack or the frame, or embedded at the individual solar module level. Bonanno says the inverter is five times more reliable, five percent more efficient and costs 20 percent less than traditional “string” inverters, which have been used for decades. The potential of a lower inverter cost, is that the entire cost of the solar system could be lower, in addition to the recent dramatic drop in solar module prices.
Empower Micro Systems doesn’t plan to manufacture the inverter box itself. The company is a fabless chip firm and it sells its integrated circuits and architecture design to manufacturers like inverter makers and solar module producers. In that respect it’s adopting Intel’s mode,
churning out the chips inside the inverter devices.
Bonanno is pretty confident of the disruptive power of the inverter tech, called the “Universal Micro Power Inverter.” He thinks it can “replace all solar inversion options, hands down.” The key technologies of the inverter are how the system on a chip synchronizes and controls the power flow at a low voltage, as well as the design of the inverter box itself.
Microinverters use energy storage tech to temporarily store the DC power from the solar panel and decouple it from the AC grid power. The Empower Micro System’s inverter uses a next-gen solid state capacitor for this energy storage tech, while other systems more commonly use more traditional liquid-filled electrolytic capacitors.
The next steps for any startup are bringing this hardware to market. Bonanno says the company has already signed one agreement with a “top-three” module maker, and is in discussions with many more module makers and power supply vendors. Just this Sunday, Bonanno said the company’s field trials went live with solar installers. This year the inverter will be certified and could be produced in pilot production by the third quarter of 2013.
The technology has attracted a list of angel investors including Jurgen Krehnke, recent President & General Manager of SMA Americas, Ken Lawler, General Partner at Battery Ventures and Silicon Ventures, Kiki Tidwell, Kauffman Fellow and cleantech investor, and Eugene Zhang, Managing Director at Tsinghua University Executive Entrepreneur Club. Chinese module manufacturers will be key for the company’s market strategy. Empower Micro Systems is currently in the process of raising a $5.5 million series A round.
There’s a lot of competition in the solar inverter space. Not only are there the new microinverters companies like Enphase Energy, and power optimizer tech from the likes of Solar Edge and Tigo Energy, but also the traditional inverter giants like SMA dominate the market. The company will need to launch and scale to prove a competitive edge.
But Empower Micro Systems plans are actually even more audacious than just replacing solar inverters. The technology can be applied to energy storage and electric vehicles, and Bonanno says one day down the road they hope to move into those markets, too.
Updated at 3PM PST, to fix the spellings of Jon Bonanno, and Jurgen Krehnke.